Through-the-wall-imaging (TWI) can be used to detect objects in a scene behind a wall. That is, the objects are positioned inside a structure enclosed by walls are detected from outside the structure. In a typical application, one or more transmit antennas emit radar pulses. The radar pulses propagate through the wall, are reflected by the object as echoes. The echoes are acquired by one or more receive antennas. The echoes are then processed using a radar imaging system or methods to generate a radar image represents positions and reflectivities of the objects.
However, depending on the dielectric permittivity and permeability of the walls, the echoes are often corrupted by indirect secondary reflections from the walls, which result in ghost artifacts that cause a noisy reconstructed image. Denoising the image can significantly improve the quality of TWI.